E-services refer to the services offered over the Internet. The globalization of economy accelerates the provision of e-services across organizations. Instead of being built from scratch, e-services are mostly extended from existing internal workflows or information systems. In this paper, we examine the requirements of extending a work-flow to the provision of e-services, in order to fulfill predefined business processes and data requirements. We also discuss the support of exception handling and asynchronous events across organizational boundaries, through an event publish-and-subscribe mechanism. We demonstrate the feasibility of this approach with the E-ADOME extension layer of our ADOME-WFMS, further illustrated with a system integration example. Our event-driven execution model provides a unified framework for both synchronous execution of workflow and asynchronous handling of events and exceptions. Illustrations are also given on the provision of such e-services over the infrastructure of Web services and Enterprise JavaBeans.